JP2003148600A - Electric range switching device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the convergence ability of feedback control in an electric range switching device which feedback-controls a motor in order to coincide the angle of a manual shaft with the target angle corresponding to a range. SOLUTION: A time constant is set from power voltage of a motor and temperature (S6, S7). The angle of the manual shaft responding by the time constant for the switch of the target angle is presumed (S8). The correction value is set based on the deviation between the presumed angle and the actual angle of the manual shaft (S9). The feedback control values (S4, S5) operated based on the deviation between the actual angle and the target angle corresponding to the required range are corrected by the correction value (S10).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric range switching device for an automatic transmission having a structure in which a manual shaft is driven by a motor to drive a manual valve.

[0002]

2. Description of the Related Art Conventionally, when a motor is operated based on a range switching request and the manual shaft rotates to a position near an angle corresponding to a target range, feedback is performed so that the angle of the manual shaft becomes an angle corresponding to the target range. An electric range switching device for an automatic transmission, which is configured to be controlled and stopped, is known (Japanese Patent Laid-Open No. 7-305).
770, etc.).

[0003]

By the way, the transient response when the motor is operated based on the range switching request changes due to the influence of the power supply voltage and temperature of the motor.
Due to the variation in the transient response, overshoot or hunting may occur, and the convergence to the target angle corresponding to the target range may deteriorate.

The present invention has been made in view of the above problems, and an automatic transmission capable of ensuring convergence to a target angle even if the transient response of the motor changes due to disturbances such as power supply voltage and temperature. It is an object of the present invention to provide an electric range switching device.

[0005]

Therefore, according to the invention of claim 1, the manual valve is driven by the manual shaft which is rotationally driven by the motor.
In an electric range switching device for an automatic transmission, which feedback-controls a motor so that an angle of a manual shaft becomes a target angle corresponding to a required range, in a manual response of a manual shaft in a transient response based on the target angle and a predetermined time constant. The configuration is such that the angle is estimated and the motor is corrected and controlled according to the deviation between the estimated angle and the actual angle.

According to the above configuration, the angle change of the manual shaft with respect to the target angle change is estimated based on a predetermined time constant, and the motor is corrected and controlled according to the deviation of the actual angle with respect to the response characteristic. The deviation from the transient response (ideal response) due to the constant is corrected so as to be closer to the response (ideal response) due to the time constant. According to the second aspect of the present invention, the time constant is stored in advance as a value suitable for the reference power supply voltage and the reference temperature state of the motor.

According to the above configuration, the angle of the manual shaft at the time of transition is estimated based on the time constants when the motor power supply voltage and the motor temperature that affect the transient response are in the reference state, and the estimated angle By correcting the deviation, the response is approximated to the reference power supply voltage and the reference temperature. According to the invention of claim 3, the time constant is changed according to the power supply voltage of the motor.

According to the above construction, the angle change of the manual shaft is estimated corresponding to the transient response which changes depending on the power supply voltage, and the motor is corrected and controlled according to the deviation between the estimated angle and the actual angle. , Try to approach the ideal response at the power supply voltage at that time. In the invention according to claim 4, the time constant is changed according to the temperature of the motor.

According to the above construction, the angle change of the manual shaft is estimated corresponding to the transient response which changes depending on the motor temperature, and the motor is corrected and controlled according to the deviation between the estimated angle and the actual angle. , So that it approaches the ideal response at the motor temperature at that time. According to a fifth aspect of the invention, the time constant is changed according to the power supply voltage and temperature of the motor.

According to the above configuration, the angle change of the manual shaft is estimated in response to the transient response that changes depending on the power supply voltage and temperature of the motor, and the motor is corrected according to the deviation between the estimated angle and the actual angle. By controlling, the ideal response at the power supply voltage and temperature at that time is approximated.

[0011]

According to the first aspect of the present invention, the transient response of the angle change of the manual shaft is corrected so as to be close to the ideal response with the predetermined time constant. Therefore, in the feedback control to the target angle, the transient response There is an effect that it is possible to avoid the occurrence of overshoot and hunting due to variations.

According to the second aspect of the present invention, the power supply voltage and temperature, which are the main factors causing the fluctuation of the transient response, are corrected so as to approach the ideal transient response in the reference state. In a normal state close to the reference state, ideal response characteristics can be obtained without being affected by other disturbances, overshoot / hunting can be suppressed, and convergence to the target angle can be improved. effective.

According to the third aspect of the present invention, the ideal transient response at the motor power supply voltage at that time is approximated to the actual transient response affected by other disturbances. As a transient response suitable for the motor power supply voltage, it is possible to avoid the occurrence of overshoot / hunting due to the fluctuation of the motor power supply voltage, and thus it is possible to improve the convergence to the target angle. .

According to the invention described in claim 4, the ideal transient response at the motor temperature at that time is approximated to the actual transient response affected by other disturbances. Therefore, even if there are various disturbances, As a transient response suitable for the motor temperature,
There is an effect that it is possible to avoid the occurrence of overshooting / hunting due to the fluctuation of the motor temperature, and thus to improve the convergence to the target angle.

According to the fifth aspect of the present invention, the ideal transient response at the power supply voltage and temperature at that time is approximated to the actual transient response affected by other disturbances. As a transient response suitable for the power supply voltage and temperature, it is possible to avoid the occurrence of overshoot / hunting due to fluctuations in the power supply voltage and temperature.
There is an effect that the convergence to the target angle can be improved.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a system configuration diagram of an electric range switching device for an automatic transmission according to an embodiment. In FIG. 1, a motor 2 as an actuator of an electric range switching device is attached to an automatic transmission 1 for a vehicle.

A deceleration mechanism 3 is provided on the output shaft of the motor 2, and the manual shaft 4 is rotationally driven via the deceleration mechanism 3. A detent mechanism 5 for positioning the manual shaft 4 at angles corresponding to a plurality of ranges is attached to the manual shaft 4. As shown in FIG. 2, the detent mechanism 5 includes a detent lever 5A and a detent lever 5A that are fixed to the manual shaft 4 and rotate integrally.
A detent spring 5B that supports a roller that engages with a recess formed corresponding to each range on the periphery of the manual shaft, and that biases the roller toward the notch. Position at an angle corresponding to any of the R range, N range, D range, 2 range, and 1 range.

The rotational movement of the manual shaft 4 is
By engaging the detent lever 5A with the manual valve 6 (spool valve), the movement of the manual valve 6 is converted into the axial movement of the manual valve 6, and the manual valve 6 is displaced in the axial direction of the valve body 7, thereby opening and closing the hydraulic port. The frictional engagement elements are switched to control the release / fastening of the friction engagement elements for setting each shift range.

A cam 9 is attached to the other end of the rod 8 whose one end is attached to the detent lever 5A.
The parking pole 10 supported so as to be swingable is driven to swing by the sliding contact with the cam 9, and at the P range position, the claw 10a of the parking pole 10 meshes with the recess 11a of the parking gear 11 to cause the parking gear 11 to move.
Is fixed.

The manual shaft 4 is provided with a potentiometer 21 for detecting the angle of the manual shaft 4, and an inhibitor switch 22 for detecting which of the ranges is selected. Further, a range select switch 23 is provided for detecting which range of P, R, N, D, 2, 1 is selected by the A / T select lever operated by the driver.

Signals from the potentiometer 21, the inhibitor switch 22 and the range select switch 23 are sent to an A / T control unit (A / T C / U).
24 is input. The A / T control unit 2
4 determines the range selected by the driver based on the signal from the range select switch 23, and sets the manual shaft 4 (manual valve) at a position corresponding to the range.
The motor 2 is controlled based on the actual angle detected by the potentiometer 21 in order to drive the motor 2.

Further, the A / T control unit 2
A detection signal of an oil temperature sensor 25 that detects the temperature of the ATF (automatic transmission fluid) of the automatic transmission 1 is input to 4. Further, the A / T control unit 24 is adapted to monitor the voltage VB of the battery 26 which is the power source of the motor 2.

Hereinafter, the A / T control unit 2 will be described.
The details of the motor control by 4 will be described with reference to the flowchart of FIG. In step S1, the range selected by the driver is determined from the signal from the range select switch 23. In step S2, the target angle of the manual shaft 4 corresponding to the selection range determined in step S1 is set.

In step S3, the actual angle of the manual shaft 4 detected by the potentiometer 21 is input. After step S3, the processing of steps S4 and 5 and the processing of steps S6 to 9 are executed in parallel.
In step S4, the deviation Er between the target angle and the actual angle is calculated.
Calculate r (Err = target angle−real angle).

In step S5, the feedback control signal of the motor 2 is set by the proportional / integral / derivative control (PID control) based on the deviation Err. Until the absolute value of the deviation Err becomes less than or equal to a predetermined value, open control (feed-forward control) for outputting a fixed control signal corresponding to the required rotation direction to the motor 2 is performed, and the absolute value of the deviation Err is When the PID becomes less than a predetermined value,
It may be configured to start feedback by control.

Feedback control is proportional, integral, and
The configuration is not limited to the differential control, and a configuration using sliding mode control or the like may be used. On the other hand, in step S6, the battery voltage VB that is the power supply voltage of the motor 2 and the ATF temperature that correlates with the temperature of the motor 2 are detected. In step S7, the battery voltage VB and AT
The battery voltage VB and A detected in step S6 is referred to by referring to a map in which the time constant T is stored in advance in accordance with the F temperature.
The time constant T corresponding to the TF temperature is retrieved.

The time constant T indicates the step response of the angle of the manual shaft 4 to the start of the operation of the motor. As shown in FIG. 4, the time constant T is longer as the temperature is higher, and As shown in FIG. 5, the lower the power supply voltage, the longer the time. In step S8, the angle during the transient response is estimated assuming that the angle of the manual shaft 4 changes according to the time constant T obtained in step S7 with respect to the step change of the target angle.

In step S9, the potentiometer 21
Based on the deviation between the actual angle detected in step S8 and the transient response angle estimated in step S8, a correction value for setting the actual angle close to the angle estimated in step S8 is set. In step S10, a total value of the feedback control signal and the correction value is calculated as a final control signal, and in the next step S11, the final control signal is a drive circuit for controlling power supply to the motor 2. Output to.

The time constant in the step response of the angle of the manual shaft 4 varies depending on the power supply voltage of the motor 2 and the temperature, but the angle estimated in step S6 is the battery voltage which is the power supply voltage of the motor 2. V
It is estimated according to the time constant T based on the ATF temperature that correlates to the temperatures of B and the motor 2. Therefore, the angle estimated in step S6 indicates an ideal response that allows for a change in the time constant depending on the power supply voltage and temperature of the motor 2, and the actual response to the ideal response is a disturbance other than the power supply voltage and temperature. If there is a deviation, the correction value absorbs the deviation and is corrected so that the angle changes with the ideal response at the power supply voltage and temperature at that time, so the occurrence of overshoot / hunting is avoided, and the target The convergence to the angle can be improved.

In the flow chart of FIG. 3, the time constant T is set from the power supply voltage and the temperature.
Alternatively, as shown in the flowchart of FIG. 7, the time constant T can be set only from the power supply voltage and the temperature.
As shown in steps S6A and S7A of the flow chart of FIG. 6, when the time constant T is set only from the power supply voltage (battery voltage VB), the ideal transient response at the power supply voltage at that time causes other disturbances ( Since it approximates to the actual transient response affected by the temperature (including temperature), the ideal response can be controlled with a simple configuration and the convergence to the target angle is improved, especially when the power supply voltage greatly affects the transient response. Can be made.

Similarly, as shown in steps S6B and S7B of the flowchart of FIG. 7, when the time constant T is set only from the motor temperature (ATF temperature), the ideal transient response at that temperature is Since it approximates the actual transient response affected by other disturbances (including the power supply voltage),
Especially when temperature greatly affects the transient response,
It is possible to control the ideal response with a simple structure and improve the convergence to the target angle.

Further, step S in the flowchart of FIG.
As shown in FIG. 7C, the time constant T may be given as a fixed value. As the fixed value, the reference power supply voltage (reference battery voltage) and the reference temperature state (reference ATF) of the motor 2 may be used.
It is preferable to store a value suitable for the temperature) in advance.
With such a configuration, if the actual power supply voltage and temperature are in a normal state close to the reference state, ideal response characteristics can be obtained without being affected by other disturbances. -Hunting can be suppressed and the convergence to the target angle can be improved.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing an electric range switching device of an automatic transmission.

FIG. 2 is a perspective view showing a drive mechanism of a manual shaft.

FIG. 3 is a flowchart showing a first embodiment of motor control.

FIG. 4 is a diagram showing a correlation between motor temperature and time constant.

FIG. 5 is a diagram showing a correlation between a power supply voltage of a motor and a time constant.

FIG. 6 is a flowchart showing a second embodiment of motor control.

FIG. 7 is a flowchart showing a third embodiment of motor control.

FIG. 8 is a flowchart showing a fourth embodiment of motor control.

[Explanation of symbols] 1 ... Automatic transmission 2 ... motor 3 ... Reduction mechanism 4 ... Manual shaft 5 ... Detent mechanism 6 ... Manual valve 21 ... Potentiometer 22 ... Inhibitor switch 23 ... Range select switch 24 ... A / T control unit 25 ... Oil temperature sensor 26 ... Battery

Claims (5)

[Claims] 1. A structure in which a manual valve is driven by a manual shaft rotationally driven by a motor,
In an electric range switching device for an automatic transmission that feedback-controls the motor so that the angle of the manual shaft corresponds to a target angle corresponding to a required range, the transient response is based on the target angle and a predetermined time constant. An electric range switching device for an automatic transmission, comprising: estimating an angle of a manual shaft; and correcting and controlling the motor according to a deviation between the estimated angle and an actual angle. 2. The electric range switching device for an automatic transmission according to claim 1, wherein the time constant is stored in advance as a value adapted to a reference power source voltage and a reference temperature state of the motor. 3. The electric range switching device for an automatic transmission according to claim 1, wherein the time constant is changed according to a power supply voltage of the motor. 4. The electric range switching device for an automatic transmission according to claim 1, wherein the time constant is changed according to the temperature of the motor. 5. The electric range switching device for an automatic transmission according to claim 1, wherein the time constant is changed according to a power supply voltage and a temperature of the motor.